A dental restoration or dental filling is a dental restorative material used to restore the function, integrity and morphology of missing tooth structure. The structural loss typically results from caries or external trauma (collectively referred to herein as cavities). It is also lost intentionally during tooth preparation to improve the aesthetics or the physical integrity of the intended restorative material.
Dental cements are used for a variety of dental and orthodontic applications, including use as luting agents, pulp-protecting agents or cavity-lining material. Furthermore, they are used to form an insulating layer under metallic, resin or ceramic restorations, and protect the pulp from injury. This helps in sealing or fixing and casting inlays, onlays, or any such substance to both dentin and enamel.
Resin cements usually have two categories: total-etch and self-adhesive resin cements. For proper use, pure resin cements require pretreatment of the tooth surface, preferably with phosphoric acid and application of a dentin and enamel primer prior to application of the resin cement. After curing this forms a micromechanical bond to both dentin and enamel. Also, they are insoluble in oral fluids. There are 2 types of these “traditional resin cements” (those that require the use of the “total-etch technique and dentin adhesive technology”) that are commonly used—dual-cured and light-cured versions. The most recent addition to the “resin cement family” are the self-adhering resin cements that require no pretreatment of the tooth surface and appear to have many of the clinical advantages of traditional resin cement systems, with the ease of use of more traditional types of cements. It is important to note that, in general, bond strengths of self-etching resin cements are not as high as those for resin cements using the total-etch technique and, as a result, may more likely lead to microleakage at the margin.
An ideal dental cementation material may provide strong and durable cementation and ease of use.